Refer to Problems 34 and 35.
a. In each case, consult the appropriate graphs to decide whether using the Wilcoxon signed-rank test is reasonable for performing a hypothesis test for the mean of the population from which the data were obtained. Give reasons for your answers.
b. For each case where using either the z-test or the t-test is reasonable and where using the Wilcoxon signed-rank test is also appropriate, decide which test is preferable. Give reasons for your answers.
Refer to Problem 34 and 35,
a. The normal probability plot and histogram of the data are depicted in Fig. 9.49 on the next page; σ is known.
b. The normal probability plot and stem-and-leaf diagram of the data are depicted in Fig. 9.50 on the next page; σ is unknown?
FIGURE 9.50 Normal probability plot and stem-and-leaf diagram for Problem 35

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